UScholar Works
 
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CreatorTitleDescriptionSubjectDate
151 Torti, Sylvia D.; Coley, Phyllis D.Vesicular-arbuscular mycorrhizae in two tropical monodominant treesMycorrhizae, symbioses between plant roots and fungi, are in virtually all terrestrial plant ecosystems. Substantial evidence indicates that mycorrhizal associations are beneficial to both partners. In most systems, the fungus benefits the host plant by effectively scavenging nutrients and in return...Monodominance; Ectomycorrhizae; Flooding; Neotropics; Vesicular-arbuscular mycorrizae; Mora excelsa; Prioria copaifera1997
152 Coley, Phyllis D.Vesicular-arbuscular mycorrhizae in two tropical monodominant treesMycorrhizae, symbioses between plant roots and fungi, are found in virtually all terrestrial plant ecosystems. Substantial evidence indicates that mycorrhizal associations are beneficial to both partners.Ectromycorrizae; Flooding; Monodominance; Neotropics; Vesicular-arbuscular mycorrhizae; Mora excelsa; Prioria copaifera1997
153 Henderson, Thomas C.Visual target based wall pose estimationWe compare vision and sonar techniques for the recovery of wall pose. A vision algorithm is developed which is based on known target geometry, and a sonar technique based on a wedge model is described.wall pose; vision algorithm; wedge model1997
154 Kessler, Robert R.Visual threads: the benefits of multithreading in visual programming languagesAfter working with the CWave visual programming language, we discovered that many of our target domains required the ability to define parallel computations within a program. CWave has a strongly hierarchical model of computation, so it seemed like adding the ability to take a part of the hierarchy ...Visual threads; multithreading; CWave1997
155 Goller, FranzVocal gestures of shared syllable types in cardinalsIn songbirds, songs are learned by memorization and copying of tutor song and such copies can be remarkably accurate. However, it is not known whether acoustic similarity is generated by equally similar vocal gestures. We studied syringeal and respiratory motor patterns of syllable types shared by u...Cardinalis cardinalis; Vocal gestures; Birdsong syllables; Song syllables1997
156 Olivera, Baldomero M.; McIntosh, J. Michaelα-Conotoxin MII blocks nicotine-stimulated dopamine release in rat striatal synaptosomesActivation of presynaptic nicotinic acetylcholine receptors (nAChRs) can induce the release of neurotransmitters such as dopamine and norepinephrine in the CNS. Accumulating evidence suggests that distinct nAChR subtypes are involved; however, it has been difficult to determine the subunit composit...Conotoxins; a-Conotoxin MII1997
157 Liu, Feng(BAl12)Cs: a cluster-assembled solidFirst-principles calculations on the geometry and stability of AlnBm clusters have been carried out to examine the effect of size, composition, and electronic-shell filling on their relative stability. It is shown that although Al and B are both trivalent, a BAl12 cluster is more stable than an Al1...First-principles calculations; (BAl12)Cs; Cluster-assembled; AlnBm clusters1997-06
158 DeTar, CarletonAssorted weak matrix elements involving the bottom quarkAs part of a larger project to estimate the fB decay constant, we are recalculating fstatic B using a variational smearing method in an effort to improve accuracy. Preliminary results for the static BB parameter and HQET two point functions are also presented.Bottom quark; Decay constants; HQET; Effective field theory1997-02
159 Vardeny, Zeev ValentineCooperative emission in ∏-conjugated polymer thin filmsPicosecond dynamics of exciton emission and absorption have been studied in neat thin films of a variety of poly (phenylene vinylene) derivatives. We found that the stimulated emission band of 120 nm width and ~1 ns duration, which is observed at low exciton density n, collapses at n > 1017 cm-3 int...Pi-conjugated polymers; Poly (phenylene vinylene) derivatives; PPV derivatives; Cooperative emission1997-01
160 Landesman, Bruce M.Decent society (book review)Review of the book `The Decent Society,' by Avishai Margalit.Books; Philosophy1997-07
161 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Dispersion of resonant Raman scattering in ∏-conjugated polymers: role of the even parity excitonsResonant Raman scattering dispersion of the most strongly coupled phonon frequencies with the excitation laser photon energy is measured in terms of a dispersion rate parameter D and quantified in a variety of p conjugated polymer films. D was found to be large in nonluminescent polymers and small i...Resonant raman scattering; Even parity excitons1997-09
162 Vardeny, Zeev ValentineElectroabsorption spectroscopy of luminescent and nonluminescent ∏-conjugated polymersWe have measured the quadratic electroabsorption (EA) spectrum of a variety of soluble luminescent and nonluminescent p-conjugated polymer films in the spectral range of 1.5-4.5 eV. The luminescent polymers include MEH and DOO derivatives of poly(phenylene-vinylene), poly(phenylene ethylene), and ...Electroabsorption spectroscopy; pi-conjugated polymers1997-12
163 DeTar, CarletonEquation of state for two flavor QCD at Nt=6We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)21 and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)21. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms ...Phase transitions; Quark-gluon plasma; Chiral symmetry1997-06
164 DeTar, CarletonEquation of state for two flavor QCD at Nt=6We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)21 and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)21. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms ...Phase transitions; Quark-gluon plasma; Dynamical quarks1997-06
165 Vardeny, Zeev Valentine; Gellermann, WernerExciton dynamics in soluble poly(p-phenylene-vinylene): toward an ultrafast excitonic switchWe have applied a variety of ps transient and cw optical techniques to elucidate the dynamics, absorption, and emission properties of excitons in soluble derivatives of poly(p-phenylene vinylene) neat films and dilute solutions. We found that the photogenerated singlet excitons in both films and sol...Exciton dynamics; Excitonic switch1997-06
166 DeTar, CarletonExotic hybrid mesons with light quarksHybrid mesons, made from a quark, an antiquark and gluons, can have quantum numbers inaccessible to conventional quark-antiquark states. Confirmation of such states would give information on the role of "dynamical" color in low energy QCD. We present preliminary results for hybrid meson masses using...Hybrid mesons; Kogut-Susskind quarks; Wilson quarks1997-02
167 DeTar, CarletonExotic mesons in quenched lattice QCDSince gluons in QCD are interacting fundamental constituents just as quarks are, we expect that in addition to mesons made from a quark and an antiquark, there should also be glueballs and hybrids ~bound states of quarks, antiquarks, and gluons!. In general, these states would mix strongly with th...Hybrid mesons; Antiquarks1997-12
168 DeTar, CarletonFinite temperature lattice QCD with clover fermionsWe report on our simulation of finite temperature lattice QCD with two flavors of O(a) Symanzik-improved fermions and O(a2) Symanzik-improved glue. Our thermodynamic simulations were performed on an 83 × 4 lattice, and we have performed complementary zero temperature simulations on an 83 × 16 la...Wilson quarks; Clover fermions1997-02
169 DeTar, CarletonImproving flavor symmetry in the Kogut-Susskind hadron spectrumWe study the effect of modifying the coupling of Kogut-Susskind quarks to the gauge field by replacing the link matrix in the quark action by a ‘‘fat link,'' or sum of link plus three-link paths. Flavor symmetry breaking, determined by the mass difference between the Goldstone and non-Goldston...Kogut-Susskind quarks; Flavor symmetry; Fat links1997-02
170 Gondolo, PaoloIndirect neutralino detection rates in neutrino telescopesNeutralinos annihilating in the center of the Sun or the Earth may give rise to a detectable signal of neutrinos. We derive the indirect detection rates for neutrino telescopes in the minimal supersymmetric extension of the standard model. We show that even after imposing all phenomenological and e...Neutralinos; Neutrino telescopes; Relic density; Annihilations1997-02
171 Olson, Randall J.; Crandall, Alan S.; Mamalis, NickIntraoperative miotics and posterior capsular opacification following phacoemulsification with intraocular lens insertionBACKGROUND AND OBJECTIVES: Posterior capsular opacification (PCO) is a frequent complication following phacoemulsification with intraocular lens (IOL) implantation. A series of consecutive patients receiving capsular bag-fixated, silicone IOL implants were assessed for both incidence of PCO and the ...Intraocular Lens; Nd:YAG Laser Capsulotomy; Miochol; Miostat; Phacoemulsification; Posterior Capsular Opacification1997-11
172 Wu, Yong-ShiMaster ward identity for nonlocal symmetries in D = 2 principal chiral modelsWe derive, in path integral approach, the (anomalous) master Ward identity associated with an infinite set of nonlocal conservation laws in two-dimensional principal chiral models.1997-11
173 Gelfand, Donna M.Mother-toddler interaction patterns associated with maternal depression.Interactive coordination was observed in laboratory play interactions of pairs of 29 clinically depressed and 14 nondepressed mothers and their 13-29-month-old children (M = 18.9 months). Nondepressed mothers and their children displayed more interactive coordination than depressed-mother dyads (p <...Depression; Child-rearing; Infants; Motherhood1997-09
174 Gondolo, PaoloNeutralino relic density including coannihilationsWe evaluate the relic density of the lightest neutralino, the lightest supersymmetric particle, in the minimal supersymmetric extension of the standard model. For the first time, we include all coannihilation processes between neutralinos and charginos for any neutralino mass and composition. We u...Neutralinos; Charginos; Higgsinos; Relic density; Coannihilations; Boltzmann equation1997-08
175 Wu, Yong-ShiNoncommutative geometry and D-branesWe apply noncommutative geometry to a system of N parallel D-branes, which is interpreted as a quantum space. The Dirac operator defining the quantum differential calculus is identified to be the zero-momentum mode of the supercharge for strings connecting D-branes. As a result of the calculus, Con...1997-04
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